Sum, Group Concat and Join with 3 tables. - mysql

Question

I am working on a tool to administer customer and payment data.
I use MySQL and have the following tables: customers and payments:
customers:
ID | invoiceID | supreme_invoiceID
1 123 a123
2 124 a123
3 103 a103
4 110 a110
payments:
ID | supreme_invoiceID | amount | date
1 a123 10 10.10.2010
2 a103 105 10.11.2017
3 a123 5 11.10.2010
And my result should look like this:
view_complete:
ID | supreme_invoideID | number_invoices | GROUP_CONCAT(invoiceID) | SUM(payments.amount) | GROUP_CONCAT(payments.amount)
1 a123 2 123;124 15 10;15
Unfortunately, I cannot get it directly into one table. Instead I create 2 views and query the payments table separately for aggregate data on payments.
First, I create an auxiliary view:
CREATE VIEW precomplete as
SELECT *, COUNT(supreme_invoiceID) as number_invoices FROM customers
GROUP BY supreme_invoiceID;
Then, a second one:
Then I take a second VIEW
CREATE VIEW complete AS
SELECT precomplete.*, SUM(payments.amount)
LEFT JOIN payments p ON precomplete.supreme_invoiceID = p.supreme_invoiceID
GROUP BY precomplete.supreme_invoiceID;
And the concatenated Values I receive in an additional query. But I would like to receive my data all in one query and hopefully, without such view hierarchy. PhpMyAdmin is already pretty slow in loading my views even with few entries.
Any help is greatly appreciated.
Thanks!

Answer 1

The db design forces an approach which builds the aggregates separately to avoid duplicates before joining on a common field for example
drop table if exists c,p;
create table c(ID int, invoiceID int, supreme_invoiceID varchar(4));
insert into c values
(1 , 123 , 'a123'),
(2 , 124 , 'a123'),
(3, 103 , 'a103'),
(4 , 110 , 'a110');
create table p(ID int, supreme_invoiceID varchar(4), amount int, date varchar(10));
insert into p values
(1 , 'a123' , 10 , '10.10.2010'),
(2 , 'a103' , 105 , '10.11.2017'),
(3 , 'a123' , 5 , '11.10.2010');
select c.*,p.*
from
(select min(c.id) minid,count(*) nofinvoices,group_concat(c.invoiceid) gciid, max(supreme_invoiceid) maxsid
from c
group by supreme_invoiceid
) c
join
(select group_concat(supreme_invoiceid) gcsid, sum(amount),group_concat(amount),max(supreme_invoiceid) maxsid
from p
group by supreme_invoiceid
) p
on p.maxsid = c.maxsid
order by minid
;
+-------+-------------+---------+--------+-----------+-------------+----------------------+--------+
| minid | nofinvoices | gciid | maxsid | gcsid | sum(amount) | group_concat(amount) | maxsid |
+-------+-------------+---------+--------+-----------+-------------+----------------------+--------+
| 1 | 2 | 123,124 | a123 | a123,a123 | 15 | 10,5 | a123 |
| 3 | 1 | 103 | a103 | a103 | 105 | 105 | a103 |
+-------+-------------+---------+--------+-----------+-------------+----------------------+--------+
2 rows in set (0.15 sec)
Much like your view approach. Note there doesn't appear to be a customer in the customer table